The proposed research investigates the growth of language and reading skills during the elementary school years in a group of 40 children with unilateral pre- or perinatal lesions (PL) whose preschool language development has been studied longitudinally since the preschool years. By continuing to follow the same group of children during elementary school, we have a unique opportunity to investigate whether functional plasticity for early language skills extends to more complex oral and written language skills. In Study I, we examine language and reading development from kindergarten through 4th grade in relation to children's lesion characteristics. Together with the preschool data, this will provide language growth trajectories from 14 months to 10 years. In Study 2, we examine how brain-injured children use gesture to support more complex language skills, and whether they use gesture in a compensatory manner. In Study 3, we use hierarchical linear modeling to examine the importance of children's preschool growth trajectories, preschool input, and lesion characteristics in predicting their later language and reading development. The data collected in Projects I and II will serve as a normative base for these studies of brain-injured children. This research will add to our knowledge about development in the face of early brain injury in several ways. First, it will provide needed information about the development of later language skills and reading in this population, skills that are important to school success. Second, it will provide information about the relation of early language trajectories to these later developing skills. Third, it will provide information about the role played by gesture in language learning. Finally, it will elucidate the joint effects of the biological characteristics of children's lesions and the language input they receive from primary caregivers on their language and reading development. The research has theoretical as well as practical implications. With respect to theory, our studies will help delineate the limits and extent of functional plasticity, allowing us to determine whether the plasticity observed for early language processes in the face of PL extends to more complex language and reading. With respect to application, characterizing the nature of caregiver-child language interactions that are effective in promoting the language skills of brain-injured children has obvious implications for intervention efforts.